While working on How's your Perl?, I was trying to find a way to create a blessed object without using bless. I stumbled across a couple:

open my $foo, ">&=STDOUT"; $foo = *$foo{IO}; print ref $foo
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creates a IO handle with class IO::Handle (but doesn't actually load that module, which would violate the rules). (For backward compatibility, the class is actually FileHandle if you have used FileHandle and IO::Handle otherwise.)

Then I recalled a less intrusive way to do it:

select(select(my $foo)); $foo = *$foo{IO}; print ref $foo
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There is actually a perl core module that uses this; I put the code there because I wanted to have a test in the core for this way of creating an IO handle without open, etc.

Unfortunately, this creates a second-class object. It doesn't honor overload in IO::Handle or FileHandle:

{ package FileHandle; use overload q[""]=>sub {"string me!"} }
select(select(my $foo)); $foo = *$foo{IO}; print "$foo";
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gives FileHandle=IO(0xa05c058) instead of the desired "string me!".

Then a little browsing through the perl source brought this builtin way to do it:

{ package PerlIO::Layer; use overload q[""]=>sub {"string me!"} }
$foo = PerlIO::Layer->find("raw");
print "$foo";
# Update: this only works for 5.8.x (actually only tested on 5.8.2)
# and not even then if you've built a perl without layers support.
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Again, this doesn't actually load any module or use bless, but this time the overloading works. (Obviously overload itself is a module, but it is a pure perl module and you can duplicate how it works; getting that to work under use strict may be troublesome, but I think it is possible.)

My current attempts at answers are on my scratch pad. I've so far avoided looking at other's answers while I haven't given up hope on the remaining problems, so please no spoilers here (though comments on my answers so far would be nice).

Update: removed useless BEGIN's, double print